We describe a new specific method for measuring lecithin, sphingomyelin, and phosphatidylglycerol in amniotic fluid by thin-layer chromatography, with use of a hydrogen flame ionization detector. After extraction and acetone precipitation to isolate surface-active lecithin, the phospholipids are separated on a thin rod of refractory and chemically stable material, having an outer coating of a b...

Residual solvents are organic volatile impurities that can occur in the manufacture of Active Pharmaceutical Ingredients (APIs). analysis pharmaceutical products is necessary not only because they represent a potential risk for human health due to their toxicity and undesirables side effects, but also may affect physicochemical proprieties product. The main objective this work was 29 residual s...

A simplified method for following the urinary excretion of estriol, pregnanediol, and pregnanoloneduring the course of pregnancy is presented. The procedure has been used successfully in a large hospital laboratory. An important advantage is that the estrogen and progesterone metabolites are measured simultaneously, and separate extraction and gas-liquid chromatographyis not required. The urine...

The zinc-cadmium oxide (ZnO-CdO) nanocomposites with different weight percentages of cadmium oxide (CdO) nanoparticles were successfully synthesized by the sonochemical method using zinc and cadmium nitrates as precursors to probe their nano-structured surfaces for the decomposition reactions of chloroethyl phenyl sulfide (CEPS) as a surrogate of sulfur mustard agent simulant. Scanning electron...

A rapid simulated distillation method is described for analysis of petroleum fractions boiling within the range of ASTM D2887 [1]. The method employs an Agilent 6890N gas chromatograph (GC) equipped with a split/splitless inlet, flame ionization detector (FID), oven insert, and 3-meter 180-μm id capillary column. A SIMDIS software package is partially integrated into the GC ChemStation for data...

The chemical composition of oregano essential oil of different origin extracted from oregano plants grown in south-eastern Poland was analysed using the gas chromatography mass spectrometry (GC-MS) and gas chromatography flame ionization detector (GC-FID). The dominant compound was sabinene; its percentage proportion ranged from 10.85% to 25.46%, depending on the ecotype studied. Moreover, the ...

This preliminary study presents a new method for the determination of dissolved gases in sea-water. After headspace extraction, gaseous compounds are separated by GC on a dual column adsorption system. The individual species are thereafter eluted to three different detectors (thermal conductivity, flame ionization and FPD) using a second switching valve. The analysis is quantitative for methane...

simple, cheap and green protocol for effective conversion of alcohols to corresponding carbonyl compounds in the presence of h14[nap5w30o110] and ammonium nitrate is reported. the products were characterized by ft-ir and comparison of their physical properties with those reported in the literatures. the progress of the reaction was monitored by thin layer chromatography (tlc) technique. the ali...

Comprehensive two-dimensional gas chromatography (GCxGC) offers an interesting tool for profiling bacterial fatty acids. Flow modulated GCxGC using a commercially available system was evaluated, different parameters such as column flows and modulation time were optimized. The method was tested on bacterial fatty acid methyl esters (BAMEs) from Stenotrophomonas maltophilia LMG 958T by using para...

A gas chromatographic method is described for the direct quantitative determination of the partial pressure of halothane (or isoflurane) in blood as well as the blood-gas partition coefficient. A head space technique and a flame ionization detector were used. Standard blood was obtained by equilibrating patients' blood with known gas concentrations in a tonometer. Using an infra-red analyser to...